Pressure-sensitive adhesive sheet and release film-supported pressure-sensitive adhesive sheet

Abstract

Provided is a PSA sheet having a PSA layer. The PSA sheet has a first face and a second face. The first face is a first adhesive face formed of one surface of the PSA layer. The first adhesive face has a 10-point mean roughness of 1000 nm or less. The PSA layer has a storage modulus of 0.08 MPa or greater at 100° C.

The invention claimed is: 
     
       1. A release film-supported pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive sheet and a first release film,
 wherein the pressure-sensitive adhesive sheet comprises a pressure-sensitive adhesive layer comprising a (meth)acrylic polymer accounting for more than 50% by weight of polymers in the pressure-sensitive adhesive layer, 
 the pressure-sensitive adhesive sheet has a first face and a second face, 
 wherein the (meth)acrylic polymer comprises, as a monomeric component constituting the (meth)acrylic polymer, a monomer having at least either a hydroxy group or a carboxy group, 
 the monomer having at least either a hydroxy group or carboxy group accounting for 15% by weight to 30% by weight of all monomeric components, 
 the first face is a first adhesive face formed of a first surface of the pressure-sensitive adhesive layer, 
 the first adhesive face has a ten-point mean roughness of 1000 nm or less, 
 the first release film is placed on the first adhesive face, 
 the first release film has a first release face in contact with the first adhesive face and the first release face has a 10-point mean roughness of 1200 nm or greater, 
 the pressure-sensitive adhesive layer has a 100° C. storage modulus of 0.08 MPa or greater, and 
 the pressure-sensitive adhesive layer has a 23° C. storage modulus of 0.15 MPa or greater. 
 
     
     
       2. The release film-supported pressure-sensitive adhesive sheet according to  claim 1 , wherein the pressure-sensitive adhesive layer has a ratio of its 100° C. storage modulus to its 23° C. storage modulus of 35% or greater. 
     
     
       3. The release film-supported pressure-sensitive adhesive sheet according to  claim 1 , wherein the pressure-sensitive adhesive layer has a 23° C. storage modulus of less than 0.30 MPa. 
     
     
       4. The release film-supported pressure-sensitive adhesive sheet according to  claim 1 , wherein the (meth)acrylic polymer comprises, as a monomeric component constituting the (meth)acrylic polymer, an alkyl (meth)acrylate having an alkyl group with 2 to 18 carbons at the ester end. 
     
     
       5. The release film-supported pressure-sensitive adhesive sheet according to  claim 4 , wherein the alkyl (meth)acrylate having an alkyl group with 2 to 18 carbons at the ester end accounts for 30% by weight to 70% by weight of all monomeric components. 
     
     
       6. The release film-supported pressure-sensitive adhesive sheet according to  claim 1 , wherein the (meth)acrylic polymer further comprises, as another monomeric component constituting the (meth)acrylic polymer, an alicyclic monomer. 
     
     
       7. The release film-supported pressure-sensitive adhesive sheet according to  claim 6 , wherein the alicyclic monomer accounts for 20% by weight to 50% by weight of all monomeric components. 
     
     
       8. The release film-supported pressure-sensitive adhesive sheet according to  claim 1 , wherein the (meth)acrylic polymer further comprises, as another monomeric component constituting the (meth)acrylic polymer, a polyfunctional monomer, wherein the polyfunctional monomer accounts for 3% by weight or less of all monomeric components. 
     
     
       9. The release film-supported pressure-sensitive adhesive sheet according to  claim 1 , wherein the (meth)acrylic polymer is a product of UV polymerization of the monomeric components. 
     
     
       10. The release film-supported pressure-sensitive adhesive sheet according to  claim 1 , wherein the second face is a second adhesive face. 
     
     
       11. The release film-supported pressure-sensitive adhesive sheet according to  claim 10 , wherein the second adhesive face has a 10-point mean roughness of 2000 nm or less. 
     
     
       12. The release film-supported pressure-sensitive adhesive sheet according to  claim 11 , wherein the 10-point mean roughness of the second adhesive face is 1000 nm or less. 
     
     
       13. The release film-supported pressure-sensitive adhesive sheet according to  claim 10 , wherein the first adhesive face has a 10-point mean roughness and the second adhesive face has a 10-point mean roughness, with either one of the two being 500 nm or less. 
     
     
       14. The release film-supported pressure-sensitive adhesive sheet according to  claim 10 , wherein the second adhesive face is formed of a second surface of the pressure-sensitive adhesive layer. 
     
     
       15. The release film-supported pressure-sensitive adhesive sheet according to  claim 1 , wherein the second face is a second adhesive face, and further comprising a second release film placed on the second adhesive face. 
     
     
       16. The release film-supported pressure-sensitive adhesive sheet according to  claim 1 , wherein the second face is a second adhesive face, and further comprising a second release film placed on the second adhesive face, and the second release film has a 10-point mean roughness of 1000 nm or less.